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Patented lune 20, |899. E. J. WDULF.

AIR AND GAS ENGINE.

(Application filed Sept. 19, 1898.)

4 Sheets-Sheetl 2.

(No Model.)

MMM/ No. 627,220. Patented lune 20, |899. E. J. WUULF.

, AIR AND GSENG'INE.

(Application filed Sept. 19, 1898.)

. 4 Sheets-Sheet 3.

(No Model.)

me Noam: Pncns co,. :Nom-umn., wAsmNaToN. u4 c.

E. Jv. w'ooLF. AIR AND GAS ENGINE.

(Application led Sept. 19, 1898.)

Patented luvne 20, `l899|.

(No Model.) 4 Sheets-Sheet 4.

I N 7 Fiji .mz Normas PETERS co, PHOTO-umn.. wAsHwGTuN. u. c.

i `II`ED t ATES f ATENT trici-3.

ELLIS J. VOOLF, OF MINNEAPOLIS, MINNESOTA, ASSIGNOR TO THE WOOLF VALVE GEAR COMPANY, OF SAME PLAGE.

AIR AND GA S ENGINE.

SPECIFICATION forming part of Letters Patent No. 627,220, dated June 20, 1899.

Application filed September 19J 1898. Serial No. 691,332. (No model.)

To a/ZZ whom it may concern:

Be it known that I, ELLIS J. VOOLF, a citizen of the United States, residing at Minneapolis, in the county of Hennepin and State of Minnesota, have invented certain new and useful Improvements in Airand Gas Engines; and I'do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertai ns to make and use the same.

My invention relates to air and gas engines, and has for its object to improve the construction with a view of increased efficiency.

To this end my invention consists of the novel devices and combinations of devices hereinafter described, and defined in the claims.

The invention` is illustrated in the accompanying drawings, wherein like notations refer to like parts throughout the several views.

Figure 1 is a perspective view illustrating a colnpound engine embodying the preferred form of my invention. Fig. 2 is a vertical cross-section of thesame substantially on the line m2 .r2 of Fig. 3. Fig. 3 is a vertical section lengthwise of the crank-shaft or substanytially on the line :r3 x3 of Fig. 2. Fig. 4E is a sectional elevation in a plane lengthwise of the crank-shaft or substantially in the same plane as Fig. 3, illustrating the compound engine equipped with a modified form of my improvement; and Fig, 5 is a detail showing a face view of the valve-gear cam detached.

The numerals 1, 2, and 3 represent flangecastings which are set one on top of the other in the order named and are bolted or otherwise rigidly secured together. The said castings l, 2, and 3 cooperate to form the base and the cylinder castings of the engine. The casting 3 is shown as having rigidly secured thereto a casting @which serves as a cross-head guide, as will later more fully appear. The casting 3 is provided at its lower end with a head 5, which serves as the partition or division-head between the high-pressure cylinder 6 and the low-pressure cylinder 8 and which head 5 is recessed to afford the explosion-chamber 7. The casting 2 and the head 5 in the casting 3 5o are formed with hollow walls, which cooperate toyafford a water-jacket 9, surrounding a portion of the high-pressure cylinder G and of the explosion-chamber 7. The water is kept circulating through the jacket 9 by any suitable connections. (Not shown.)

In the high and low pressure cylinders 6 and S are located corresponding high and low pressure pistons 10 and 12 on a common rod 11. To the low-pressure piston 12 is secured a cross-head 13, which works in the casting 4t as a guide. The cross-head 13 is connected by a rod 14 to the crank-disk 15 on the crankshaft 16. The castings 1 and 2 are so f ormed as to afford a bearing for said crank-shaft 1G. The crank-disk 15 is shown located at one end of the shaft 16, and the opposite end of the shaft 16 is provided with a suitable fly-wheel 17, which also may be used as the pulley for transmitting the power to any point desired. On the shaft 16, adjacent to the fly-wheel 17, is mounted a cam 18, which operates on one arm of a rockerlQ, which is pivoted to the casting 2, with its arms extending approximately in the vertical plane. This cam 18 and rocker 19 constitute the valve-gear for controlling tbe distribution-valves in a manner which-will later be described. The end of the shaft 16 adjacent to the ily-wheel 17 is reduced, as shown at 16a. On the same is loosely mounted a shipper or reversing, sleeve 20, which has attached to its inner end a key 21. The valve-gear cam 18 is loose on the shaft 16, but may be made fast thereto for rotation therewith by the key 21. For this purpose the ca'm 1S is provided on its face withapair of key-seats 22 at the opposite ends of an incomplete or segmental groove 23, countersunk in the hub of the cam. rlhe shipper or. reversing sleeve 2O is recessedfto receive a spring 24, which reacts between the baseof the recess of said sleeve and the reduced end 16a of the shaft, to which the outer end of the spring is made fast in any suitable way. The spring 24, reacting against the shaft 16 `as a base of resistance, tends to hold the sleeve 2O and the key 21 in their innermost positions, but when it is desired to reverse the engine the said sleeve 2O and key 21 can be drawn outward, thereby permitting the shaft to revolve, while the cam 13 remains stationary until the inner end of the key 2l passes from one end of the groove 23 to the other,

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thereby iinding entrance to the opposite meinber of the two key-seats 22. Just how this reverses the engine will appear later when tracing the operation.

The high-pressure piston and the rod 11 are recessed or formed hollow for cooperation to afford a mixing-chamber for the air and gas. As shown, agasolene-tank 26 is secured to the casting 4, and from the saine a valvepipe 27 depends into the bore of the hollow rod l1. Said supply-pipe 27 is shown as provided with a hand-valve 28. As shown, the said pipe27 has formed integral therewith a solid extension 27 at its lower end, and at the junction of the hollow and solid sections the pipe-section 27 is provided with small perforations b vfor the outlet ot' the gasolenef With this construction the solid section 27n serves as a distribnter for the gasolene. The parts 27 and 27 are of course of smalldiameter compared to the bore of the hollow rod 1l, and this rod being open at its upper end a'tfords an abundance ot clearance or space for the entrance of air. The said hollow piston 10 is provided with avalve 29, controlling a port opening to the compression end of the high-pressure cylinder. The said valve 29 is shownas provided with a light spring 30 sutlicient to overcome the gravity of the valve for holding the same to its seat.

The base-casting 1 is formed hollow to atford a storage chamber 3l. This storagechamber 3l is provided with valve-controlled ports opening to the opposite ends ofthe highpressure cylinder 6. As shown, the casting 2 is provided with a recess 33, which is always in communication with the recess 31 in the base-casting 1 through a suitable passage connecting the same. A port c leads from the compression end of the high-pressure cylinder l5 to the valve-chest 33 and is under the control of a gravity-valve 34, as shown in Fig. 2. The upper end of the chest 33 is provided with a port d, opening to the explosion-chamber 7v anduinder the control of a valve 35. The valve 35 is provided with a downwardlyextended guide-stem 36, which carries at its lower endias a nut an angular bracket 37. A spring 38 reacts against said bracket 37 and one wall of the chest 33 for holding the valve 35 to its seat against the pressure from the storage-chamber 31. A hand-shaft 39 extends into the chest 33 through the chestplug 41 and is provided on its inner end with an eccentric 40, which may be brought into action on the bracket 37. The said parts 39 and constitute a hand device by which the valve 35 may be held in its open position for admitting storage-pressure to the cylinders when desired for starting the engine, as will later more fully appear.

The valve has a flanged head 42,`which overreaches the upper end of the piston 10 for causing' the piston 10 to raise the valve 35 into its open position at the limit of said pistons upward stroke. The said valve 35 also serves as one member of the electrodes vfor the electric igniter.

The other member 43 is fixed to and insulated from the upper end of the piston 10 at a part of the same underlying the flange 42 on the valve 35. This insulated electrode 43 is provided with a-n insulated wire 44, leading to one-pole of a suitable battery or other source. The Valve 35 and the engine-castings are connected with the other pole of the battery or source by suitable connections, which in the present instance include a circuit maker and breaker subjectto the action of the reversing device for opening the igniter-circuit independent of the electrodes when the engine is reversed. For this purpose, as shown, the wire 48 from the battery to the engine-castings is attached or seated in an insulating-ring 45, carried on the shipper-sleeve 20. The insulating-ring 45 is loose on the sleeve 20-and has a pin 4G engaging a groove 47 in said sleeve. The wire 48 is seated in the inner profile face of said ring 45 and is normally held in contact with the hub of the fiy-wheel 17 under the action of the spring 24,; but when the shippersleeve 2O is pulled outward, as required for reversing the engine, the insulating-ring 45 and the wire 48 will be carried with it, thereby opening the circuit between the wire 4S and the fly-wheel 17. The purpose of this will more fully appear in tracing the operation of the engine. The wire 48 would be held, of course, in practice in any suitable way to prevent the sleeve or ring 45 from turning with the crank-shaft.

A portfleads from the explosion-chamber 7 to the portf, which leads to the low-pressure cylinder S. The portf is under the control of a valve 49, which opens inward. The port or passagef is tapped by a iinal exhaustportf?, leading to a valve-chest 5l, tapped by the iinal exhaust-pipe 52. The final exhaustport f2 is controlled by a valve 50, which opens outward. The said 'valves 49 and 50 are in line with each other and open in oppositedirections against acommon retractionspring 53. As shown, the valve is recessed and the spring 53 encircles the stem of the valve 49 between the base of the recess in the Valve 50 and a head 54 on the stem ot' the valve 49. The spring 53 therefore serves to seat both valves. This spring 53 must be of sufficient tension to resist the pressure from the low-pressure cylinder S. The valve 50 is slotted to receive the upper end of the upper arm of the rocker 19, forming a part of the valve-gear. The rocker-arm entering the valve 50 works between the head 54 on the valve 49 and the outer head ot' the valve 50, opening said valves alternately in opposite directions, at the opposite limits of the rocker-s throw, under the control 0f the cam-wheel 1S.

Operation Assume that the engine has been started and that the storage-chamber 3l contains air and gas at workin g pressure. Then during the upstroke of the pistons 10 and 1.2 a charge will be drawn in from thleJ mix- TOO IIO

ing-chamber 25 through the hollow rod 11 and delivered into the compression end of the high-pressure cylinder 6, the valve 29 opening for this purpose Linder the vacuum produced behind the piston 10. On the downstroke of the pistons the said charge will be compressed within the compression end of the high-pressure cylinder 6 until it exceeds the pressure in the storage-chamber 31, and when that point is reached the valve 34 will open, thereby permitting the charge to be forced into the storage-chamber 31 under the continued downward movement of the highpressure piston 10. At the limit of said highpressure pistons downward stroke the valve 34 closes by gravity, thereby holding the charge'or confining the same-within the storage-chamber 31. On the next upward movement of the pistons the charge being traced is held confined under pressure in the storage-chamber 31 until the high-pressure piston 10 approaches the limit of its upward stroke, whereupon the said piston 10 acting on the flange42 of the valve 35 will raise the same, thereby opening the port d from the storage into the explosion chamber 7 and admitting the charge thereto. Then when the pistons again start downward the valve 35 first closes under the action of the spring 38,

and then the insulated electrode 43 on the piston separates from the flange 42 of the valve-electrode 35, thereby producing the spark and causing the explosion. The working stroke of the high-pressure piston then takes place, and during the same the charge which had been drawn into the compression end of the high-pressure cylinder during the last previous upstroke of the piston is compressed into the storage-chamber in the same way as the charge originally traced. Upon the completion of said high-pressure stroke the valve-gear will open the valve 49, thereby permitting the partly-spent gases to pass through the ports f f into the low-pressure cylinder S. The low-pressure stroke then takes place, and at its completion the valvegear will open thefinal exhaust-valve 50, therebyperrnitting the final exhaust through the ports f and f2 into the chest 51 and out through the exhaust-pipe 52. At this time the valves will all be in the positions illustrated in Figs. 2 and 3 of the drawings ready for another explosion.

In the foregoing statement a charge has been traced from its entrance through the mixing-chamber 25 through all the subsequent steps of its storage and use to the point of final exhaust. In order to trace a single original charge in the manner above stated, it was necessary to follow through more than one cycle of the engine actions. One highpressure and one low-pressure stroke of course complete one cycle of the engines action.A

Every stroke of the pistons is a working stroke. At everylow-pressure stroke a charge is drawn from the mixing-chamber 25 into the compression end of the high-pressure cylinder 6, and at every high-pressure stroke this charge is compressed into the storagechamber 3l. The charge thus compressed into the storage-chamber 31 under the working high-pressure stroke is held in said storage-chamber 31 under pressure during the followingloW-pressure stroke, and at the completion of the low-pressure stroke a charge is admitted from the storage to the explosion chamber to be exploded for the next working high-pressure stroke.

From the foregoing statements it must be obvious that in this engine the compression of the charge or unexploded gases takes place under the explosion or high-pressure stroke. This of course is a radical dilferen ce over the ordinary standard gas-engine, wherein the compression takes place under the momentum of the moving parts. Hence by properly proportioning the parts of this engine the effective pressure on the crank may be kept substantially uniform under both the high and the low pressure strokes without regard to the question of momentum in the moving parts. It follows that with this engine a small fly-wheel is sufficient. Otherwise than for reversing, which will now be described, a fly-wheel would be no more needed than on a steam-engine.

The reversing action-It has already been stated that to reverse the engine it is only necessary-to pull the shipper-sleeve 2O into its outermost position, and that thereupon the cam-wheel 18 will stand stationary while the shaft continues to turn until the key 21 rides from one end to the other of the groove 23, so as to rengage the opposite member of the key-seats 22 in the cam-wheel18. When this shift has taken place, the parts will be IOC) properly related to make the valve actions come right after the engine has reversed. Directing attention now to the reversing action, let it be assumed that the engine was in motion and the shift of the sleeve 2O took place when the parts were all in the positions shown in Figs. 2 and 3. The distributionvalves 49 and 50 would then remain in the positions shown in said Figs. 2 and 3 while the pistons made their downstroke. Thereupon the distribution-valves 49 and 50 again becoming subject to the valve-gear as set for reversing will open and close in the reverse order of time. In virtue of this change in the timing the exhaust-valve 50 remains open during the next upstroke of the pistons under the momentum of the moving parts, and thereby permitting air to be drawn in through the ports f2 and j" into the low-pressure cylinder 8. On the next downstroke of the pistons, continuing under the momentum of the moving parts, the final exhaust-valve 50 being closed and the valve 49, controlling the port f, being open, the air and gases in the explosion-chamber 7 and the low-pressure cylinder 8 will first equalize and then be compressed into the high-pressure cylinder t3 on the explosion side of the high-pressure pis- IIO ton 10 and will there be held when the valve 49 closes. These same actions Will be repeated until the air thus pumped into the two cylinders and compressed equals or eX- ceeds the momentum of the moving parts. As quick as this occurs the engine will stop and reverse under the pressure thus accumulated in the two cylinders. The valve motions having been set to come right under this reversed mot-ion of the engine the engine will continue to run in the opposite direction under Working pressures from explosions.

The reversing action of the engine herein disclosed, as above described, is identical with the reversing action of the engine disclosed in my pending application, Serial No. 634,182, filed April 27, 1897, and allowed No- Vember 29, 1898, entitled Air and gas engine,and in the said pending application, Serial No. 634,182, I have broadly claimed the construction whereby this result is accomplishedas a pioneer invention.

The presence of a circuit maker and breaker operated by the reversing device for opening the igniter-circuit independently of the igniter-electrodes, as hitherto described, is an important feature in relation to the reversing action, of this engine. By that provision,

whereby the circuit is opened, Whenever the shipper-sleeve 2O is thrown into its outermost position no further explosion can take place until said shipper-sleeve is released and the key 2l is reseated inthe opposite member of the seats 22 at the opposite limit of the groove 23 in the cam-wheel 18. Explosion is thereby avoideduntil desired for the vworking stroke in the reverse direction of the engine, and no explosion can take place back in to the storagechamber 3l under the action of the igniterelectrodes and the opening of the valve 35.

Starting-In the foregoing description of the operation it was assumed that the engine had been started. From that description it must be obvious that whenever the engine stops the storage-chamber 31 will contain air and gas under` working pressure. Hence whenever it is desired to start the engine all that is necessary is to manipulate the hand device 39 and 40, thereby raising the valve 35 and admitting storage-pressure to the cylinders under the control of the distributionvalves 49 and 50. The parts are so proportioned that when the eccentric 40 of the hand device is in its highest position acting on the bracket 37 the valve 35 will be raised to an extreme position, so as to afford clearance between the iiange 42v thereof and the other member 43 of the igniter-electrode, so as to avoid explosion until after the engine has started.

The modified construction illustrated in Fig. 4 diifers from the construction shown in the other views and hitherto described in certain features, which will now be noted. In this modification the high-pressure piston p, rod p, low-pressure piston p2, and cross-head p3 are all hollow and in communication with chamber p4.

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each other for cooperation to form a storage- The high-pressure piston p is provided with a gravity-valve p5, controlling a port p6, opening to the compression end of the high-pressure cylinder 6, and is also pro- J' vided with a spring-seated valve p7, controlling a port p8, opening into the explosionchamber 7. The stem of the valve p7 projects through a guide-passage in the upper wall of the piston p in position to strike the insulated member p9 of the pair of igniterelectrodes, one of 'which is afforded by the valve p7. In this instance the Xed electrode p9 is secured to the upper wall of the eXplosion-ehamber 7 and suitably insulated therefrom, as in the other form the valve p7 receives current lfrom the engine-casting, The charge is admitted to the compression end of the high-pressure cylinder 6 through an inlet q from a mixer of the ordinary or any suitable kind, the position of which is shown in dotted lines only at q in Fig. 4.

Having regard to the action, the material difference is due to the location of the storage-charnberl)4 in the moving parts @19'192193 instead of in a separate reservoir independent of the moving parts of the engine, as in the other form. In view of this difference in the location of the storage-chamber the storage is not available in the construction shown for starting the engine. of its location it would be inconvenient to provide access to the storage-chamber with a suitable hand device, such as would be required for starting purposes. The valve p7, controlling the ,port p8, is held to its seat by a spring p10, which must y.be of sufficient tension to withstand the explosion-pressure within the chamber 7 less the storage-pressure in the chamber p4.

Having regard to both forms,'it will be convenient to distinguish the valves which control the inlet and outlet ports to and from the storage-chamber as the charging-valves for convenience of comparison with the distribution-valves 49 and 50, which, of course, are subject to the valve-gear.

It will be understood that many of the details might be changed and that the principal features of the invention are capable of considerable modification in construction andarrangement without departing from-the principle of my invention.

What l claim, and desire to secure by Letters Patent of the United States, is as follows:

1. A gas-engine having a storage-chamber into `which the' charge is compressed during each explosion stroke of the piston, and is held under pressure during each exhaust stroke thereof, and from which said charge is admitted, under pressure, to the explosionchamber at the completion of said exhaust stroke, in combination with suitable valve mechanism for controlling said action, including an admission-valve to the explosionchamber operated by the piston, substantially as described.

On account IIO ISO

2. In a gas-engine, the combination with a cylinder closed at both ends and a piston working` therein, of a storage-chamber having ports to both ends of said cylinder, and Valve mechanism controlling said ports, with all of said parts so arranged that the charge is compressed into said storage-chamber by the piston during the explosion stroke, is held therein under pressure during the exhaust stroke of the piston, and is admitted, under pressure, to the explosion-chamber, at the con1- pletion of said exhaust stroke, and which Valve mechanism includes an admission-valve to the explosion-chamber operated bythe piston, substantially as described.

3. In a gas-engine, the combination with a cylinder closed at both ends to form compression and explosion chambers at its opposite ends, of a hollow piston and rod serving as a mixing-chamber for the air and gas and provided With a valve-controlled port opening to the compression end of the cylinder, and a storage-chamber with Valve-controlled ports to both ends of said cylinder, all for coperasaid distribution-valves mounted to seat opposite to each other and connected for opposite movementsagainst a common retractingspring, and a single Valve-gear operating both of said valves, substantially as described.

5. In a compound gas-engine, the combination with vthe high and loW pressure cylinders set tandem, the high-pressure cylinder being` closed at both ends to form compression and ELLIS J. VOOLF.

Wtn esses:

JAS.l F. WILLIAMSON, B. B. NELSON. 

